Poster Presentation Australian Diabetes Society and the Australian Diabetes Educators Association Annual Scientific Meeting 2016

Mechanical noise improves the vibration perception threshold of the foot in people with diabetic neuropathy (#331)

Jaap J. van Netten 1 , Jennefer B. Zwaferink 2 , Klaas Postema 3 , Juha M. Hijmans 3
  1. Queensland University of Technology, Kelvin Grove, QLD, Australia
  2. Ziekenhuisgroep Twente (Hospital Group Twente), Almelo and Hengelo, the Netherlands
  3. University Medical Center Groningen, Groningen, the Netherlands

Objective: Reduced somatosensation of the foot is the greatest risk factor for diabetic foot ulceration. Mechanical noise, administered as random vibrations from specific insole elements, may improve somatosensation at the dorsal side of the foot, as shown in pilot studies. However, the effect of on somatosensation at the plantar side of the foot, the side most at risk for foot ulceration, is unknown. Moreover, techniques used in research so far have several problems that limit applicability in daily practice. The aim of the current study was to determine the effects of mechanical noise generated by piezo-electrodes on vibration perception threshold (VPT) at the plantar side of the foot in people with diabetic neuropathy.
Research design and methods: A double-blind cross-over within-subjects design in a controlled laboratory setting. Forty participants with diabetic neuropathy were included. VPT was measured at three locations of the plantar side of the foot with and without mechanical noise via piezo-electrodes.
Results: Mechanical noise improved the VPT at metatarsophalangeal joint (MTP) 1 (left foot 39.3V vs. 43.5V; right foot: 39.0 vs. 42.6 V; both p<.001), MTP5 (left foot 37.5V vs. 41.7V; right foot: 34.5V vs. 40.8V; both p<.001) and the heel (left foot 40.0V vs. 44.0V; right foot: 39.3V vs. 41.0V; both p<.001).
Conclusion: Mechanical noise improves VPT at the plantar side of the foot in patients with diabetic neuropathy. This is an important step for further development of ulcer prevention insoles for patients with diabetic neuropathy.